Effects of high-energy proton irradiation on separate absorption and multiplication GaN avalanche photodiode

The effect of high-energy proton irradiation on GaN-based ultraviolet avalanche photodiodes (APDs) is investigated. The dark current of the GaN APD is calculated as a function of the proton energy and proton fluences. By considering the diffusion, generation-recombination, local hopping conductivity, band-to-band tunneling, and trap-assisted tunneling currents, we found that the dark current increases as the proton fluence increases, but decreases with increasing proton energy.